Loam
Four terrain types, unevenly split
For this comparison, shaded means at least 60% canopy and steep means at least 5° of slope. The other groups fall below those thresholds. These are analysis categories, not trail difficulty ratings.
Half the sample fell in the shaded, gentle group. Open, steeper terrain made up 8.3%, the smallest group.
Download this study: Frozen network rows CSV | Frozen rows JSON with definitions
Examples from each group
Shaded and steep
Hartland Mountain Bike Park and Little Mountain in British Columbia had 100% canopy readings at 6.4°. Mont-Sainte-Anne in Quebec had 100% at 7.3°, and Bent Creek in North Carolina had 98% at 8.8°.
Shaded and mellow
Bear Mountain Bike Park in British Columbia had 100% canopy at 0.9°. Crothers Woods in Ontario had 100% at 3.4°. Both combined heavy tree cover with gentle terrain.
Open and steep
South Mountain Park & Preserve in Arizona had 0% canopy at 11.8°. Ridge to Rivers in Idaho and Usery Mountain Regional Park in Arizona also had 0% canopy, with slopes above 7°.
Open and mellow
Novi Tree Farm in Michigan had 56% canopy at 0.3°. Grapefruit Trail in Florida had 51% at 0.5°. Both fell below our 60% canopy cutoff, though neither was treeless.
Why aspect only sometimes changes the estimate
Aspect is the direction a slope faces. Loam applies a sun-exposure adjustment on slopes of at least 5°. Below that, the model treats aspect as neutral.
The reasoning
Slope direction has less effect on sun exposure when the ground is nearly flat. The 5° cutoff is a modeling choice, not a measured boundary between trails that dry quickly and slowly.
About 26% of this sample met the slope threshold for the aspect adjustment. Soil, recent rain, and other weather inputs still affect every network estimate.
The thresholds describe this analysis and do not define trail difficulty or a physical drying boundary. The downloads contain the exact 312 catalog rows used for the publication, with their assigned category and source commit.
About Loam estimates
Loam estimates conditions from weather, soil, and terrain. It does not measure the trail surface directly or override an official closure. Read how the estimate works and see the published checks and their limits.
